Backs for receiver cabinets



June 3, 1958 M. J. PIFER BACKS FOR RECEIVER CABINETS 2 Sheets-Sheet 1 Filed April 22, 1953 RECEIVER INVENTOR. MARION J. PIPER A770 FY June 3, 1958 I p FF 7 2,837,633

BACKS FOR RECEIVER CABINETS Filed April 22, 1953 Y 2 Sheets-Sheet 2 INVEN R MARION J. ER

ATTORNEY United BACKS F OR RECEIVER CABINETS Marion J. Pifer, Williamsville, N. Y., assignor to Sylvania Electric Products Inc, a corporation of Massachusetts This invention relates to backs for receiver cabinets.

More particularly, the invention relates to an antenna supporting back portion of a cabinet housing an electronic device, said back portion being modified to support conductors or actually having conductors supported by the back.

Specifically the invention relates to the modification of back covers for radio and television receivers for the reception of an antenna coupling coil or an antenna itself or actually having an antenna or antennae mounted thereon.

With respect to radio receivers, while initially they were not equipped with built-in antennas, the advent of higher gain tubes and improved circuitry have enabled manufacturers to provide th receiver with such an antenna. Infrequently the receiver has a built-in antenna with no provision for connection of an external antenna to the receiver except by removal of a built-in antenna lead from a terminal. Frequently radio receivers are provided with an antenna loop connected to the receiver input and ground together with a second loop inductively coupled to the receiver loop, which second loop has a terminal connection on the loop support to which an outside antenna lead may be secured. However, particularly in urban areas where the radio transmitter is close to the receiver and the received signal is strong, the possessor of the radio finds reception satisfactory without an outside antenna and does not find it necessary to install such an antenna. Therefore, in such cases, the provision of the second loop is a needless expense and waste of material.

In the case of television receivers, my invention lends itself to the easy application of high frequency antennas to the back of the receiver, whether in the V. H. F. range or the U. H. F. range or both.

It is therefore an object of the invention to provide a receiver back which shall lend itself to the easy application thereto of a conductor.

It is a second object of this invention to provide a ready means available to the possessor of a receiver to mount an outside antenna coupling loop or an outside antenna on the receiver back.

It is a still further object of this invention to cheapen rates fPatent the cost of manufacture of a radio receiver back which i electrically associated with the receiver loop.

Fig. 3 is a view, partly in section, showing a terminal utilized with my organization.

Fig. 4 is a plan view of the back cover of a television receiver, with antennas mounted thereon, as it would appear from the side which faces the television chassis, and

Fig. 5 is a side elevation of the back, part being broken away to expose inner wiring.

Referring back to Fig. 1, there is shown a radio receiver cabinet 1 having a closed back 2 of cardboard, pressed board, or other suitable insulating material, this back being secured to the cabinet by means of screws 3 or the like. The back is provided with suitable openings 4 to provide for ventilation of the cabinet, as is usual in the art and with a recessed portion 5 for the reception of the line cord 6'. The back is further provided with cut outs 6 each of which may be in the form of a crescent with a stifi tongue portion 7, integral with the back, extending radially away from the center of the back and extending diagonally toward a corner thereof. This tongue is spaced from the crescent shaped wall on all sides to permit of easy looping of wire thereabout. On the inside of this back, that is the side facing the front of the cabinet, is secured, as by the use of a suitable adhesive or overlying tape or adhesive sheet material, a signal reeciving loop indicated as 8 in Fig. 2.

One end of this loop is connected to one input terminal of the receiver, as for example the grid of an r-f preamplifier tube, and the other end is connected to the other input terminal of the receiver, as for example a so called ground connection. The ground end of the loop is also permanently secured to a terminal 9 the end of which projects through the back, i. e. to the face of the back as shown in Fig. 3. On this face the terminal is provided with a wire attaching means such as the conventional screw means it).

As pointed out heretofore, in urban areas there is seldom any need to couple an outside antenna to the receiver. However, should it be so desired, such coupling may be easily eifected by fastening an end 11 of the antenna lead-in 12 to any convenient ground connection or beneath the screw 10 and forming one or more loops on the back with the aid of the cut out and tongue portions, as will be readily understood. The coupling effected will be apparent by consideration of Fig .2 wherein the antenna lead-in is shown in inductive relation to the coil 8 and connected to the antenna 13.

By means of the simple but ingenious means herein disclosed, it is possible for the public at large to buy a set at a cheaper price, but yet, as by following simple printed instructions and at no more than the cost of a piece of wire, any lay member of the public can easily hook up his radio to an outside antenna.

The principle of looping a conductor about stiff projections, fingers or tongues set forth above may be applied to television antennas as well. Thus in Figs. 4 and 5 there is shown a back 14 of stiff insulating material such as pressed board with an opening 15 for accommodating the housing which encompasses the rear end of the neck of the television tube and a safety interlock connector 16 to which the cord connector 17 may be applied, as now conventional in the art. The back is furthermore bulged to provide inclined walls 18 and a panel 19 displaced outwardly from the chassis, to accommodate television antennas 2t) and 21. The antenna 20 is the conventional folded dipole type utilized for V. H. F. reception while the antenna 21 is the conventional bow type used for U. H. F. reception.

The bulged portion of the back is provided with four recessed portions 22, each having a finger or tongue 23 integral with the back extending thereinto. The tongue 23 is sudficiently wide and thick to enable the wire of the antenna to be trained thereabout without folding or bending of the tongue and it is spaced from the walls of the recess sufi'iciently to allow easy placing of the Wire on the back. The conductors of the bow are held in place by the fingers 23 aforesaid and by suitable terminals 24 to which the bows are electrically connected. These same terminals provide electrical connection for lead-in line 25 for the U. H. F. section of the receiver. The lead-in line passes downwardly on the inner side of the bulged back, through a diagonal slot 26 in the back to the outside thereof. Thence it passes horizontally along the outside of the back to a large opening 27 and then again through the back to the inside thereof and to the receiver U. H. F. coupler.

The folded dipole 20 is supported in part by the inclined walls of the back and in part by other portions of the back. One loop of the folded dipole has a wire lapped once around the tongue or finger 28 and thence runs upwardly inside along the inclined wall 18, then through a diagonal slot 29 to the outside; thence the wire runs under a stiff finger 30 integral with the back, in again and up to and around a finger 31, similar to finger 28. This finger 31 like the others extends into a cut out portion 32. Thereafter the wire extends horizontally along the inner face of the back to another finger 33, similar to finger 32, around the same, and then, in parallel arrangement with the first bight of the loop, extends around fingers similar to those already described back to the opening 27. Here the wire loops about the finger 34 and thence horizontally along the inner face of the back and along the inclined wall 18 at the left in Fig. 4 and back again to complete the dipole, as shown. The dipole it can therefore be seen, is fixed in position by the use of the described cut outs and fingers. To further hold the dipole in place, and so as to prevent rattles, portions of the wire intermediate the fingers may be immovably secured to the back. A suitable means for doing this is a pyroxylin cement shown as applied at the areas 35 bounded by the dotted lines in Fig. 4. The free ends 36 of the dipole 20 are led to suitable terminals on the receiver.

If so desired, the television receiver may be supplied at the factory with the back and with either both antennas thereon or only one of them, or none at all. In the latter two cases, printed instructions furnished the purchaser of the set would advise him how to apply an antenna or antennas in the event he is in a strong signal area and he does not or cannot use an outside antenna.

While I have described particular embodiments of my invention, it should be obvious that various changes may be made without departing from the spirit of my invention as defined in the following claims.

What I claim is:

1. A back panel adapted to be mounted on the rear of a radio receiver mounted in a cabinet, said back panel having mounted, on the inner face presented toward the front of the cabinet, a signal receiving loop, said loop being adapted to be connected at both of its ends to the input of the receiver, one end of the loop being connected to a terminal on the back, the terminal having a portion exposed on the other, outer, face of the back, and provided thereat with a second terminal and projections formed in the back and accessible from said outer face for winding a coil thereabout, which coil may be connected with the second terminal and an outside antenna.

2. A back for a radio cabinet, said back being substantially rectangular in plan and having an inner face presented toward the front of the cabinet and an outer exposed face, a loop signal receiving coil permanently mounted on said back on the inner face thereof and adapted to be connected at both of its ends with the input of a radio in said cabinet, a terminal extending through said back having permanent connection at its inner end with an end of the loop and having an outer terminal, said back being provided with tongues adjacent the corners of the back with the tongues extending radially from the center of the back whereby a second loop may be wound about the tongues on the outer face of the back and connected at its one end to the outer terminal and at its other end to an outside antenna.

References Cited in the file of this patent UNITED STATES PATENTS 2,292,182 Van Billiard Aug. 4, 1942 2,307,805 Schnell Jan. 12, 1943 2,318,361 Bischoff May 4, 1943 2,492,772 Van Billiard Dec. 27, 1949 2,514,992 Edelsohn July 11, 1950 2,541,818 Gruen Feb. 13, 1951 2,640,931 Root June 2, 1953 FOREIGN PATENTS 418,708 Great Britain Oct. 30, 1934 114,805 Australia Mar. 3, 1942 

